diff options
| author | Ming Lei <ming.lei@redhat.com> | 2018-11-20 09:44:35 +0800 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2018-11-21 05:57:56 -0700 |
| commit | 1db4909e76f64a85f4aaa187f0f683f5c85a471d (patch) | |
| tree | ec08842eff41be0c4db21599a2a8954019335a30 /block/blk-mq.h | |
| parent | 0c62bff1fd633774756be6d88d71002cd37615e0 (diff) | |
blk-mq: not embed .mq_kobj and ctx->kobj into queue instance
Even though .mq_kobj, ctx->kobj and q->kobj share same lifetime
from block layer's view, actually they don't because userspace may
grab one kobject anytime via sysfs.
This patch fixes the issue by the following approach:
1) introduce 'struct blk_mq_ctxs' for holding .mq_kobj and managing
all ctxs
2) free all allocated ctxs and the 'blk_mq_ctxs' instance in release
handler of .mq_kobj
3) grab one ref of .mq_kobj before initializing each ctx->kobj, so that
.mq_kobj is always released after all ctxs are freed.
This patch fixes kernel panic issue during booting when DEBUG_KOBJECT_RELEASE
is enabled.
Reported-by: Guenter Roeck <linux@roeck-us.net>
Cc: "jianchao.wang" <jianchao.w.wang@oracle.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/blk-mq.h')
| -rw-r--r-- | block/blk-mq.h | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/block/blk-mq.h b/block/blk-mq.h index facb6e9ddce4..9ae8e9f8f8b1 100644 --- a/block/blk-mq.h +++ b/block/blk-mq.h @@ -7,6 +7,11 @@ struct blk_mq_tag_set; +struct blk_mq_ctxs { + struct kobject kobj; + struct blk_mq_ctx __percpu *queue_ctx; +}; + /** * struct blk_mq_ctx - State for a software queue facing the submitting CPUs */ @@ -27,6 +32,7 @@ struct blk_mq_ctx { unsigned long ____cacheline_aligned_in_smp rq_completed[2]; struct request_queue *queue; + struct blk_mq_ctxs *ctxs; struct kobject kobj; } ____cacheline_aligned_in_smp; |